This invention is in the field of projection systems and specifically is directed to interacting with a projection display. In particular, a method and apparatus for interacting with a projection display using a pointing device such as a laser pen is disclosed.
Computers are often utilized in conjunction with projection screens or displays for presentations and meetings. For example, it is common to display a slide show that is stored within the memory of a computer onto a projection display. Typically, the person giving a presentation (a presenter) interfaces with the computer via input devices (e.g., keyboard, mouse) in order to effectuate a change on the projection screen. For example, the presenter may be seated at the keyboard and scroll from slide to slide in a slide show by striking the enter key.
Laser pointers are also widely used for meetings and presentations. For example, the presenter may use a laser pointer to draw attention to a particular area of the projection screen. As such, a slide may be projected on a projection display and the presenter may direct the laser pointer towards the display, thus causing a red dot to appear on the desired area of a display.
These conventional techniques for interacting with a projection display suffer from numerous drawbacks. When the presenter is forced to utilize computer input devices to interact with the projection display, the presenter typically remains within a close proximity of the computer system. This is because the presenter uses the computer input devices (e.g., keyboard, mouse) to interact with the projection display. This may be undesirable, as the presenter may prefer to walk around the room and not remain fixed at the computer station. Further, when utilizing a laser pointer to draw attention to the projected display, the area highlighted is only momentary. As such, the image projected on the projection display is not altered by directing a laser pointer at the image. Accordingly, a presenter cannot readily draw attention to more than one area of the projection display at a time, because once the laser pointer is moved to a new area of the display, the red dot disappears from the first area.
Therefore, it would be desirable to have a system that allows a presenter to interface with a projection display more readily, and more effectively.
Interaction with a display occurs. A light point is transmitted towards the display. A mode of operation of the light point is established based on timing associated with illumination of the light point.
In a preferred embodiment, a combined image of the light point and an image on the display is captured and processed to determine a position of the light point. The image on the display is then updated based on at least one of the position of the light point and the mode of operation of the light point.
An apparatus for interacting with a display using a light point is also disclosed. The apparatus includes timing means that determine timing associated with illumination of the light point. Control means control a mode of operation of the light point based on the timing.
In a preferred embodiment, the apparatus includes a projector to project the image onto the display. A camera is also included for capturing a combined image of the light point and an image on the display. An image processor processes the combined image to determine the position of the light point with respect to the image. Update means update the image on the display based on the position of the light point, the operational mode of the light point, or both.